The invention relates to a separation system employing a column containing a porous matrix embedded with chromatographic particles and a method of packing a channel with the matrix to make the column.
Capillary zone electrophoresis (CZE), with its high peak capacity (i.e., the number of peaks separated per unit time), has long been proven to be an attractive analytical technique for separating ionic species by their electrophoretic mobilities. The separation of neutral species via CZE, however, has remained more problematic. To improve the separation of neutral species via capillary electrophoresis, the technique of capillary electrochromatography (CEC) has been employed, which is a promising technique that seeks to combine the advantages of capillary electrophoresis and chromatography as described in the article by M. T. Dulay et al. in Chromatogr. A., 725 (1996) pp. 361-365).
In CEC, the separation of uncharged analytes is based on partitioning of chromatographic particles such as octadecylsilica, while the separations of charged analytes are based on both partitioning and electrophoretic mobility. Existing techniques for the preparation of packed capillary columns are based on either a slurry packing method or an electrokinetic packing method of small-bore capillary columns. The electrokinetic packing method may be more advantageous than a slurry packing method for the preparation of packed capillary columns with micron-sized inner diameters. Disadvantages of the electrokinetic packing method include the limited choices of chromatographic phases (i.e., only charged particles can be used) and the need for both inlet and outlet frits to prevent the chromatographic particles from leaving the capillary column. This causes the columns to be difficult and time consuming to make.
It is therefore desirable to provide a separation column with improved characteristics and that are easy to make.